Chair with spring-mounted seat element

ABSTRACT

A chair has a seat element with a seating surface, which is mounted on a leg unit. The seat element is solely connected to the leg unit by means of a spring clip.

REFERENCE TO RELATED APPLICATION

This application claims priority from German patent application No. DE 20 2008 011303.2, filed 25 Aug. 2008, the entire content of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a chair with a seat element, which is mounted on a leg unit.

Such chairs are known from practice and for example as seat element comprise a seat pan, which on the one hand forms a seating surface and on the other hand a back rest. The seat element for example is rigidly bolted to a leg unit, which forms four chair legs. The leg unit here can be designed as a tubular structure.

The object of the invention is to create a chair of the type specified at the beginning with increased seat comfort.

This object is achieved by the chair with the features of claim for protection 1.

According to the invention therefore a chair, comprising a seat element having a seating surface, which is mounted on a leg unit, is proposed. The seat element is solely connected to the leg unit by means of a spring clip.

Due to the spring clip the seat element can move in relation to the leg unit as a function of the spring action and the force acting on the seat element and follow back and forth changing weight-bearings of the user in the dimensions permitted by the design of the spring. The spring action of the spring clip thus increases the seat comfort compared to the prior art described above.

The seat element can be designed as a chair pan, configured in the usual way, with a seating surface and a backrest and comprise upholstery over its entire area or also only in parts. The leg unit can be designed in various ways and for example represent a frame, which has four chair legs or a rotating stand.

In a preferred embodiment of the inventive chair the spring clip is substantially a U shaped spiral spring, by which one side is fastened to the seat element and the other side to the leg unit. The two sides here preferably are aligned substantially horizontally, so that the spiral spring is openly configured towards the chair back.

In order to be able to provide maximum spring length or maximum spring travel the side of the spiral spring fastened to the leg unit preferably lies underneath on a cross bar of the leg unit, which in the case of a leg unit designed as a four-legged frame preferably extends between laterally arranged pairs of legs of the leg unit. The base of the U shaped spiral spring can therefore be released to the maximum by the contact of the lower side of the spiral spring from below on the cross bar in respect of its overall height.

The spiral spring, which for example has a width of approximately 8-15 cm, is preferably formed from an extruded profile with a substantially U shaped cross section. Thus it can be ensured when mass-producing the inventive chair that the spring action is uniform from chair to chair. For example the extruded profile, from which the sections are produced for the spiral spring, is drawn from aluminum or an aluminum alloy. The alloy can then be accurately composed for the required strength so that the desired spring action of the spiral spring results.

Alternatively it is naturally also conceivable to produce the spiral spring from a metal pressing or also from a suitable plastic.

For connecting the spring clip to the seat element and the leg unit the spring clip can have threaded sleeves, by means of which it is bolted to the seat element and the leg unit.

The leg unit for example consists of two curved profiles, conjoined in the region of the cross bar for connecting the spiral spring, which in each case form two chair legs and in each case are preferably fixed to the spring clip. A screw connection for joining the two curved profiles together is therefore possibly no longer necessary.

Further benefits and advantageous arrangements of the subject matter of the invention result from the description, drawings and claims for protection.

An exemplary embodiment of an inventive chair is diagrammatically illustrated in a simple way in the drawing and is explained in detail by the following description.

FIG. 1 shows a perspective view of a chair with a seat element designed as seat pan and a leg frame, wherein the seat element is illustrated transparently for the sake of clarity;

FIG. 2 shows a longitudinal section through the chair in the region of the connection of the seat pan to the side frame; and

FIG. 3 is an enlarged illustration of the connection region.

The drawing illustrates a chair 10, which has a seat pan 12, produced from a section 14 forming a seating surface and a back rest 16. As to be inferred from FIG. 2, the section 14 forming the seating surface and the backrest 16 of the seat pan 12 are each provided with an upholstery pad 18 or 20.

The seat pan 12, representing a seat element, is connected to a leg unit 24 designed as a four-legged frame by a spring clip 22, which is designed as a substantially U shaped spiral spring. The leg unit 24 is formed from two curved profiles 26 and 28, each bent similar to the drop handlebars of a bicycle, which have a substantially square cross section and form two of the four chair legs respectively. The two curved profiles 26 and 28 conjoin in their respective middle sections for forming a cross bar 30. In the region of the cross bar the spring clip 22 is fastened by means of two fixing screws 32 underneath to the curved profiles 26 and 28 in each case. Thus the two curved profiles 26 and 28 of the leg unit 24 are also rigidly placed against each other. The fixing screws 32 here in each case are inserted in a threaded sleeve 34 of the spring clip 22 in the region of its lower, substantially horizontally aligned side 36.

The spring clip 22 in the region of its upper, substantially horizontally aligned side 38 has four threaded sleeves 40, into which a screw 42 is inserted from above in each case for connecting the seat pan 12 to the spring clip 22. The screws 42 are covered or concealed by the upholstery pad 18.

The threaded sleeves 34 and 40 in each case are designed as so-called sunken castellated nuts, whose conical section is inserted into a corresponding hole of the spring clip 22 in each case, so that the screws 42 covered by the upholstery 18 and the screws 32 can be locked.

The spring clip 22 has a width of approximately 10 cm and is formed from an extruded profile made of an aluminum alloy. The open side of the U shaped spring clip, related to a conventional chair direction, points to the rear and enables the seat element 12 to spring back and forth.

As overload protection a buffer element 44 consisting of a flexible material, rubber for example, is arranged in the region of the cross bar 30 on its top, which serves as a stop for the upper side 38 of the spiral spring 22 whenever the seat element 12 bears a heavy weight.

The spring clip 22 is produced by drawing an extruded profile made of an aluminum alloy with a U shaped cross section, that is to say with the cross section of the spring clip 22 and by subsequent cutting to length of the extruded profile into sections of 10 cm for example. 

1. Chair, comprising a seat element having a seating surface, which is mounted on a leg unit, characterized in that the seat element is solely connected to the leg unit by means of a spring clip.
 2. Chair according to claim 1, characterized in that the spring clip is substantially a U shaped spiral spring, by which one side is fastened to the seat element and the other side to the leg unit.
 3. Chair according to claim 2, characterized in that the side, fastened to the leg unit, of the spiral spring lies underneath on a cross bar of the leg unit, which preferably extends between laterally arranged pairs of legs of the leg unit.
 4. Chair according to claim 3, characterized in that the leg unit consists of two curved profiles conjoined for forming the cross bar, which in each case form two chair legs and are preferably connected to the spiral spring in each case.
 5. Chair according to anyone of claim 1, characterized in that the spring clip is formed from an extruded profile with a substantially U shaped cross section.
 6. Chair according to claim 2, characterized in that the spiral spring has a width of approximately 8-15 cm.
 7. Chair according to anyone of claim 1, characterized in that the spring clip is an aluminum component or an aluminum alloy component.
 8. Chair according to anyone of claim 1, characterized in that the spring clip preferably has threaded sleeves made of steel, by means of which it is bolted to the seat element and the leg unit. 